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81.
Qi Haikun Wang Sai Xu Dongyong Lu Zhengying Zhao Wenchao Hao Yanjie Zhang Xiang Li Wei Han Huanyong Wang Jiangtao Wang Hongzhe Chen Hongzhang Wang Lin Du Mingwei Tian Xiaoli Li Zhaohu 《棉花学报》2013,32(5):425-437
[Objective] The objective of this study was to investigate the stability and universality of cotton chemical topping by applying mepiquat chloride (1,1-dimethyl-piperidinium chloride, DPC) in different cotton-growing regions. [Method] Field experiments were conducted in 2018 at 10 locations in the Yellow River basin (Hejian and Handan, Hebei province; Dezhou and Wudi, Shandong province), the Yangtze River basin (Dafeng, Jiangsu province; Huanggang, Hubei province), and Xinjiang area (Shihezi location I and loacation II, northern Xinjiang and Luntai and Shaya, southern Xinjiang). Local cultivars/lines were used, and the experiments were performed using a randomized complete block design with three or four replicates. Accompanied with typical DPC multi-application in each location, chemical topping was conducted at 10 days before manual topping (T1) or at the same time with manual topping (T2) by applying four dosages of DPC (0, 90, 180, 270 g·hm-2), manual topping was used as the first control and non-topping as the second control. [Result] The time of chemical topping significantly affected cotton plant height (except for the results in Handan, Dezhou and Wudi) and the number of fruit branches (except for the results in Dafeng and Huanggang). It was observed that earlier chemical topping would result in lower cotton plant height and a fewer fruit branches. In Hejian and Shihezi location I, the average plant height across DPC chemical topping at T1 stage was not only lower than that of T2 stage but also 3.3 cm and 4.6 cm lower than that of manual topping, respectively. In most locations, chemical topping at T1 stage increased around two fruit branches per plant compared with manual topping, while in T2 stage the increased fruit branches per plant ranged from 2.3 to 7.7. Also, we found that a higher dosage of DPC resulted in shorter plant height (except for that in Huanggang). In some locations, plant heights of chemical topping with 180 g·hm-2 or 270 g·hm-2 DPC were even shorter than that of manual topping. The number of fruit branches per plant of 0 g·hm-2 DPC increased by 2.4-8.3 compared with manual topping. However, chemical topping with 90-270 g·hm-2 DPC significantly reduced the number of fruit branches compared with 0 g·hm-2 DPC. There were no significant differences in the number of fruit branches among three DPC dosages (90, 180, and 270 g·hm-2). In Handan, seed cotton yield of chemical topping at T2 stage was significantly lower than that of manual topping due to the decreased boll number, which is possibly associated with the high temperature and drought weather after chemical topping. While at other locations, most treatments of chemical topping by using DPC did not produce significant effects on yield. In addition, chemical topping by using DPC did not delay cotton maturity, characterized by their similar boll-opening rate and the first harvest rate to those of manual topping before spraying harvest aids. [Conclusion] Cotton chemical topping with DPC is more stable and universal across different cotton-growing regions. We suggest that 90-180 g·hm-2 DPC could be used at the same time with manual topping for cotton chemical topping. 相似文献
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基于电磁阀的喷嘴直接注入式农药喷洒系统 总被引:2,自引:0,他引:2
设计了一种喷嘴直接注入式农药喷洒系统。通过与传统喷雾机械比较,简述了喷嘴直接注入式喷雾系统的结构和喷雾执行单元。为了实现农药定量注入,设计一种基于电磁原理的快速响应阀,并论述其工作原理和闭环控制方式。通过试验测试了喷雾执行单元的喷雾特性和喷杆组内各喷雾单元的一致性。结果表明在一定喷洒速率范围内,喷雾执行单元的喷水量和水压强存在多项式关系,农药注入量和PWM信号的高电平时间存在指数关系,其决定系数均高于0.9,并且同一喷杆组内6个喷雾单元的喷雾效果大体一致。 相似文献
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本文通过棉花种子活力与电导率、阳离子外渗、组织结构、凝集素和种子加工的关系研究表明,种子活力下降,阳离子外渗增加,其中主要是K~+。种子各部分对逆境条件的反应不同,越是活跃的组织越易丧失活力。高活力的种子也是高凝集素的种子,在多逆抗性的选择过程中,利用低温发芽是对种子高活力和高凝集素等抗性物质的选择。因此,可考虑用电导率、胚根和下胚轴的比值作为检验棉子活力的指标。并证明棉子经我国自行研制的泡沫酸脱绒机处理,能有效地提高播种品质。 相似文献
87.
PLC监控系统在自来水厂的应用 总被引:3,自引:3,他引:3
针对自来水厂水处理的特点和工程实例,介绍了贵州铜仁自来水厂采用FX2N-128MR可编程控制器作为下位控制机实现自来水生产工艺中排泥除沙自动控制系统。分析了系统的工作原理,硬件组成,网络结构及软件设计等。结论认为:系统中PLC与PC微机的串行通信方法稳定可靠,效果良好,实现了自来水处理系统的自动化,提高了水质。 相似文献
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基于激光反射的土壤表面粗糙度测量装置设计与试验 总被引:5,自引:2,他引:5
为了实时获取土壤表面粗糙度数据,设计了一种基于激光三角测距原理的土壤表面粗糙度专用测量装置.采用激光扫描测距仪测量微位移,其精度高、响应速度快,测距分辨力高达0.1 mm,显著提高了土壤表面粗糙度的测量精度;借助于光电编码盘和螺杆组合实现高精度扫描定位;PDA作为上位机,农田环境下具有方便携带,大容量存储数据和智能化实时处理功能等优点. 相似文献